Safety, appliance for electric railways.



m. Hooves: SAFETY APPLIANCE FOB ELECTRIC RAILWAYS.

Patented July 4, I899.

(Application filed June 15, 1896.)

[No Model.)

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UNITED STATES PATENT OFF CE.

MAURICE HOOPES, OF LYNN, MASSACHUSETTS.

SAFETY,APPL|ANCE FOR ELECTRIC RAILWAYS.

SPECIFICATION forming part of Letters Patent No. 628,177, dated July 4, 1899.

Application filed June 15, 1896- To all whom it may concern.-

Be it known that I, MAURICE HOOPES, a citizen of the United States, residing at Lynn, in the county of Essex and State of Massachusetts, have invented certain new and use ful Improvements in Safety Appliances for Electric Railways, of which the following is a full, clear, and exact description.

This invention relates to electric railways of that class-in which a main insulated c'ontinuous-supply conductor or conductors is used in connection with a. sectional working conductor or conductors and wherein the sections of the working conductors are supplied with current through branch circuits extending from each section to the insulated main and each including a circuit-controller which is operated automatically by the car to close the branch circuit upon the approach of the car to any particular section and to open the said circuit when the car leaves the section. The conductors of such systems are usually placed in a subway between or adjacent to the rails or otherwise buried in the roadway; but my invention is not limited to such particular location of the conductors. It is applicable as well to overhead or suspended sectional-conductor systems as to those placed beneath the surface of-the ground. In all such systems the possibility of a section of the working conductor remaining alive after the car has'passed, when it should be disconnected or dead, exists, especially so in those systems utilizing electromagnetic apparatus to control the branch circuits.

The object of this invention is to provide means whereby the possibility of a sectional rail being left alive is overcome or at least made very much more improbable of occurring.

The invention may be carried out in vari- Serial No. 595,524. (No model.)

which each of the sections of the working con-' ductor is positively connectedwith the return-circuit at all times except when the car is passing. Fig. 2 illustrates'aplan involving two insulated main conductors, one positive and the other negative, and two lines of sectional conductors connected, respectively,

therewith and equipped with safety appli-' ances similar to those shown in Fig. l. The two main conductors of opposite polarities are represented by a and b, it being understood that one of them may be the earth or rail, or both.

Referring to Fig. 1, c c 0 &c., are the sections of the sectional conductor, with which it is understood the car makes traveling contact as it moves along to receive its propellingcurrent. (1 cl (1' are respective branch circuits from the main to to the sections of the working conductor. These branches each contain a circuit-controller e and an automatic circuit-breaker, such as a fuse f. The circuit-controller in the drawings is shown merely as a pivoted armature, it being understood that the car carries a magnet m, which lifts the armature for a given section and holds the circuit closed while the car is passing. When the car leaves the section, the armature is supposed to fall against its back-stop, and thus cut off the section from the. source of supply, making it harmless. Each section 0 c 0 &c., is normally connected with the opposite conductor 1) by means of a spring-finger g and branch wire h. As the car enters upon each section it lifts this spring-finger out of contact with the section by means of a plow g or other suitable device, so'that when the section receives current through 6 itwill pass through the car-motor. When the car leaves the section, spring-finger g makes contact automatically with the section, and if the circuit-controller c has not opened the branch (2 as it should a short circuit is established from a to b, and the automatic circuit-breaker f will then be destroyed by the heavy current and the section will be positively disconnected from the main. At

the same time if the return-conductor is the rail, the earth, or any other uninsulated conduct-or the section is brought to the safest potential and held there by the contact of the finger g. In case this automatic circuitbreaker is a fuse the flash would indicate to any one in the vicinity the fact of the faulty action of the controller 6, and the employees of the operating company could then take the necessary steps to replace the fuse and repair the circuit-controller.

In Fig. 2 the plan shown in Fig. 1 is repeated, but with a double set of conductors, there being positive and negative sectional conductors cm and cy and double sets of armatures e for the respective sectional conductors. In addition to this this figure illustrates the use of a safety-conductorm, which by being connected at short intervals with the rails and with the road-bed (it may be a bare conductor) is maintained at the same potential as the said rails and road-bed. When an armature e sticks, the contact 9 closes a circuit h to conductor m, thus bringing the section to a safe potential. For blowing the fusevarious plansmaybeadopted. Onewould be to connect m permanently with a or b or to some point havlng a potential intermediate to aand I). Then the fuses would be blown by a current from m. This intermediate potential could only be obtained'by connecting to the middle of a series of batteries 70, connected from a to b, or to the intermediate connection of two generators in series between a and b, or to the middle of a resistance between a, and b, &c. The simplest way to accomplish the blowing of the fuses would be to dispense with all connections between in and a I). Then the first sticking armature would connect its particular main with the conductor m", which might be indicated by a ground detector at the station, consisting, say, of the lam ps1), and an at tendant there would ground the opposite main a or b by throwing switch 3. .This would short-circuit and blow the fuse feeding the sticking armature; or the first sticking armature could remain closed without causing trouble, and when one stuck on the opposing conductor it would blow one or the other, or both, fuses and relieve the short circuit, the idea being that one ground or a number of grounds on one conductor cannot make trouble and that the first ground on the opposite conductor would be automatically cleared.

Having thus described my invention, I claim- 1. In an electric-railway system of the character described, the combination ofa main circuit, a sectional conductor, branches between the main and sectional conductors, and two circuit controllers or breakers in each branch, with means in the roadway for sh0rt-circuiting the sections after the passage of the car, one of said circuit-breakers being normally open and controlling the flow of working cur rent to the car, while the other is normally closed but adapted to open the circuit when the section is short-circuited, substantially as described.

2. In a sectional electric-railway system, the combination with the sections of the working conductor, of a contact device connected with the return-circuit of the system, and normally in contact with a section of the sectional cond'uctor,an automatic circuit-breaker in a branch conductor supplying current to the section, and a separate circuit-controller also in said branch conductor, substantially as described.

3. In a sectional electric-railway system, the combination with the sections of a working conductor, of a contact device connected with a conductor of opposing polarity to that of the supply-conductor and normally in contact with a section of the sectional conductor, an automatic circuit-breaker in a branch conductor supplying current to the section, and a separate. circuit controller also in said branch conductor, substantially as described.

4. In a sectional electric-railway system, the combination of a main supply-conductor, a sectional Working conductor, a branch from the main to a section of the sectional conductor, a normally open circuit-controller in said branch, a safety-conductor whose potential may be maintained atany desired value, a branch from the safety-conductor to said section of the sectional conductor, and a normally-closed circuit-controller in said lastmentioned branch,substantially as described.

In testimony whereof I subscribe my signature in presence of two witnesses.

MAURICE HOOPES. VVituesses:

ARTHUR B. PORTER, EUGENE MARLoo. 

